1. Field of the Invention
The invention relates to a shoe construction, more particularly to a dynamoelectric shoe which incorporates a pressure-operated electric generator unit for converting the energy that is exerted by the user while walking into electricity which can be used to charge a rechargeable battery cell for operating an electrical device.
2. Description of the Related Art
U.S. Pat. No. 5,167,082 by the applicant discloses a dynamoelectric shoe which comprises a shoe sole that confines a watertight compartment, a pressure-operated electric generator unit that is provided inside the watertight compartment adjacent to a heel portion of the shoe sole and that produces a voltage signal when pressure is applied repeatedly on the shoe sole during use, and a power outlet unit that includes an electrical socket mounted on the shoe sole and a rechargeable battery unit connected electrically to the electrical socket and to the electric generator unit, the rechargeable battery unit being charged by the voltage signal from the electric generator unit.
The rechargeable battery unit includes a rechargeable battery cell connected to the electrical socket, a battery charger circuit receiving the voltage signal from the electric generator unit so as to charge the rechargeable battery cell, means for deactivating the battery charger circuit so as to stop charging of the rechargeable battery cell when the voltage across the battery cell exceeds a predetermined limit, a supplementary current supplying circuit for providing additional current to the electrical socket when a plug is inserted into the electrical socket, means for detecting if the plug is inserted into the electrical socket, and means for deactivating the supplementary current supplying circuit when the plug is not inserted into the electrical socket.
The electric generator unit comprises a base plate, a press plate having a horizontal press portion and an inclined portion extending rearwardly from the press portion, one end of the inclined portion being pivoted on the base plate, a compression spring provided between the inclined portion and the base plate to bias the press plate away from the base plate, a driving shaft extending downwardly from the press portion, a speed increasing gear assembly actuated rotatably by upward and downward movement of the driving shaft when pressure is applied repeatedly on the press portion during use, and an alternator unit having a rotor driven rotatably by the gear assembly so as to produce the voltage signal. A rectifier circuit is connected to the alternator unit so as to rectify the voltage signal.